Audiologists and ENTs rely on a set of standard tests and equipment for diagnosing hearing loss and balance issues. Atypical among modern medical disciplines, little has changed in recent years technologically, aside from the equipment being connected to PCs and networked, instead of manually transcribing the results. To help smoothly navigate you or your child’s first visit, we spoke with Annie Cardello, an audiologist with Otolayrngology Specialists of North Texas, about the tests and tools you can expect.
Inside The Booth
Routine testing of older children and adults takes place in a sound booth with pure tone testing, which consists of playing tones at different intensities to see how well you hear each frequency and if you are in normal range or not. Audiologists test the acoustic reflex to see if there is a nice pull of the muscle behind the ear drum in response to loud sounds using equipment called an admittance unit, which tests the integrity of the auditory nerve.
- ENG: “We do electronystagmography (ENG) testing where we hook electrodes around the eyes and measure eye movement in response to different positions and visual stimuli to see how the balance system is responding. There are lots of reflexes that link to the eyes and inner ear, so we measure the eye to see what the balance system is doing and if it is responding appropriately.
Then we do the hearing test in the sound booth to see if there are any correlating findings,” said Cardello.Her practice’s booth also has an audiometer, a machine used for playing tones and speech signals. It also contains a tympanometer, which tests eardrum movement. The otalyrngologist then analyzes the ENG test data with other test results to determine any possible diagnoses.
- OAE: When caring for an adult with special needs or a child who can’t respond behaviorally to pure tones, audiologists do testing with otoacoustic emissions (OAE), which utilizes a hand-held device hooked up to a PC. The device has a tip that is inserted into your ear and sends tones of different frequencies into it. If you have a healthy ear, it sends back an echo that gets measured. Since this does not rely on response behavior, you can be asleep during the test.
- ABR: An Auditory Brainstem Response (ABR) system is used for children who can’t respond behaviorally to tones in the sound booth or who can’t sit still enough for an OAE procedure. It involves putting electrodes on the patient and measuring his brainwaves in response to different sounds. Although noninvasive, the procedure is frequently performed in an operating room, so the child can be sedated in order to get the best reading possible.
- BAE: A Behavioral Audiometry Evaluation (BAE) tests how a person responds to sound overall. Infants and toddlers are observed for changes in their behavior such as sucking a pacifier, quieting or searching for the sound, and they’re rewarded for the correct response by getting to watch an animated toy (this is called visual reinforcement audiometry). Sometimes older children are given a more play-like activity (called conditioned play audiometry). BAE tests the function of all parts of the ear and the person being tested must be awake and must respond to sounds heard cooperatively during this test.
For basic functions like looking into a child’s ear to see if they have a wax impaction, audiologists and physicians use a little flashlight called an otoscope, which allows doctors to see if the eardrum is healthy and if there is anything blocking the sound waves. If there is wax, a wire loop on a handle called a curette is used to clean it out.